More particularly pneumatic devices and equipment require electrical connections, in addition to pneumatic hose connections, for the transmission of electrical control signals, sensor signals and electrical power. In certain cases this may mean a relatively large number of conductors, hoses and cables make installation, servicing and repair expensive, complex and elaborate. Similar problems occur also in the case of hydraulic equipment and devices, in the case of which both fluids and also electrical signals must be transmitted.
In order to tackle this problem the German patent publication 19,827,883 A1 has for example suggested the integration of metallic conductors in the wall of a pneumatic hose. In order to maintain flexibility such conductors have to have an extremely small cross section, something which in turn means that contact means and measures must be relatively complex and involved. In order to render this possible at all the outline of the pneumatic hose must be asymmetrical in design in order to set the necessary angular position for the contact means to engage.